Front wheel bearing race not seating in hub, normal?

[donbecker1234]

First time replacing my front wheel bearings on my car.

I've pulled the passenger's side first, my smaller race went in fine, but the larger will not go any further, it looks like it's a 1/16" shy of being seated fully.

It doesn't look like it's cocked, it looks straight in.

I haven't pulled the driver's side yet, and there was a lot of grease in the passenger's side hub so it was hard to see but I think the old race was seated fully (before I removed it).

I have an aluminum billet press tool, and maxed out my Harbor Freight 20 ton press on it, and the race isn't moving.

Researching past threads on the forum here, I've found two other occurrences of this:

Does this look right? Space between front hub dust seal and spindle spacer ring

Wheel Bearing Project--Is this right?

I'm redoing my entire front suspension so it might be awhile before I can test fit to see if the race is okay in it's current location.

For the more experienced members, does anyone know if this gap is fine?

Was there ever any definitive information that this was related to a change in the hubs at some point?

[donbecker1234]

Yesterday I pulled the driver's side hub and the larger bearing race has the gap, so at this point I think the gap is normal.

The large race has the letters from it impressed on the hub, not sure if that means a large amount of force was used to originally press these. I suspect my bearings are original (like the entire suspension on my car). Large race was German, smaller race was Italian.

I grabbed some gauge blocks and measured the distance the race was in the hub.

From the back flat surface of the hub to the race, it's approx .451".

There is also a small step in the hub that is above the race. I measured .401-.402" from the back surface of the hub.

Hope this helps someone in the future.

[KTL]

Good to hear it worked out for you. Going forward, you shouldn't be pressing the races into the hub. We can heat the hub to 250-300F, which expands it and the races are then very easy to tap into the hub. Also helps to put the races in the freezer for a few hours to shrink them a bit.

Same process goes for removing the old races. Heat the hub and the greater thermal expansion of the aluminum allows the steel races to be softly knocked out of the hub with a carefully placed drift or punch and your hammer. They literally drop right out with a minimal number of taps on the drift.

I've messed with hubs that were tainted by hammering the races out and pressing them in poorly. I could see the damaged bore by the smearing of the aluminum. The set I had were harmed pretty good in order to push the races in straight, so the hubs wouldn't have excessive runout/wobbling when mounted on the strut spindle. After I got the races out, even cranking up the heat in the oven (I have a retired toaster oven) wouldn't allow the races to go in straight. They'd only go in the bore a little bit, then go crooked and stop.

I know how the hubs were wrecked because I watched my friend struggle with installing the races via a hammer & punch, race driver tool, hydraulic press around 20 years ago. This was before I was aware of the heat expansion method. He was a very handy guy and not at all a hack. But obviously the race installation didn't go well that day. Not long after I helped Mark in his struggles, I discovered the heat expansion method for my own 911 the following year when I was reading the Bentley service manual to do my front wheel bearings.

Fast forward to recent times and funny how life takes its turns. My friend's car became mine (RIP my friend) and here we go again with history repeating itself as I had to battle with the races in the hubs. Since the proper press fit was effectively destroyed, I retired those hubs and got a known good used replacement set.

I didn't want to just discard the messed up hubs and I was able to "salvage" them by using my Dremel rotary tool with a consumable felt polishing head wheel that has 600 grit abrasive in it. That cleared out the smeared aluminum and let the races go in the hubs without binding.

That said, those hubs with the loosened press fit are now labeled as NFG. The races were installed at room temperature into the room temperature hubs and they went into the hubs WAY too easy. The only good use for them right now is on a roller car i'm selling. Maybe they can be machined oversize for bearings with an oversize race OD? I'm not aware of oversize bearings for the 911 hubs and not going to bother looking......